I was doing some research about ivermectin in preventing heart worms in my beagles and thought this information at the link looked like a good conversation starter. It is only this person’s opinion, and he is not a Veterinarian. This is why inputs are needed by you. If you disagree or.you have a better method, we would like to hear it. Maybe some of us can learn something of value. Also, when we have more than 4 dogs, it gets expensive. It is my hope that this discussion will help.